High-voltage (i.e., for high voltage) wire harnesses are used as components for electrical connection between, for example, a battery and an inverter unit of a hybrid car or an electric car. Some wire harnesses for the electrical connection between the battery and the inverter unit include a plurality of high-voltage conducting paths and an exterior member for protecting these conducting paths (see Patent Document 1 identified below).
Patent Document 1: JP 2010-12868 A
In the above-mentioned prior art, an exterior member made of resin is used. The arranging location of the wire harness for use in a hybrid car or an electric car generally includes a vehicle underfloor portion. Hence, the exterior member of the wire harness may be exposed to external environment. Furthermore, the exterior member may be partially exposed to the heat of heating elements, such as an exhaust pipe and an exhaust manifold. For this reason, an expensive resin material having all of chemical resistance, abrasion resistance, heat resistance, etc. is used for conventional exterior members in some cases. In such cases, the costs for the exterior member and the wire harness increase.
In addition, in a case where the exterior member is partially exposed to heat, heat resistance is required only at some portions of the exterior member. However, since the same expensive resin material is used for the entire exterior member according to the prior art, the entire exterior member has heat resistance. As a result, portions not requiring heat resistance have heat resistance. As described above, in the exterior member according to the prior art, the characteristics of resin materials may not be fully utilized at the respective portions of the exterior member.
The present invention has been made in view of the above circumstances, and it is an object thereof to provide a wire harness exterior member and a wire harness capable of reducing cost and capable of utilizing the characteristics of resin materials at the respective portions thereof.